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Open access

Initial institutional experience using a robotic arm–enabled 4K 3D exoscope in neurosurgical operations

Jawad M. Khalifeh, Ali Karim Ahmed, Wataru Ishida, Joshua Materi, Anita Kalluri, Daniel Lubelski, Timothy Witham, Nicholas Theodore, Debraj Mukherjee, and Judy Huang

The extracorporeal telescope (exoscope) presents a novel digital camera system as a versatile alternative to traditional optical microscopy for microsurgery and minimally invasive neurosurgical operations. Recent innovations in exoscope technology offer 4K-definition multiscreen outputs, pneumatic robot arms, 3-dimensional depth perception, and greater illumination, focus, and magnification powers for enhanced intraoperative visualization. The authors present their initial institutional experience using a robotic arm–enabled 4K 3D exoscope in a variety of cranial and spinal neurosurgical operations, namely Chiari decompression, microvascular decompression for trigeminal neuralgia, anterior cervical discectomy, and lumbar decompressions.

The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23150

Open access

Robot-assisted screw fixation in a cadaver utilizing magnetic resonance imaging–based synthetic computed tomography: toward radiation-free spine surgery. Illustrative case

A. Daniel Davidar, Brendan F. Judy, Andrew M. Hersh, Carly Weber-Levine, Safwan Alomari, Arjun K. Menta, Kelly Jiang, Meghana Bhimreddy, Mir Hussain, Neil R. Crawford, Majid Khan, Gary Gong, and Nicholas Theodore

BACKGROUND

Synthetic computed tomography (sCT) can be created from magnetic resonance imaging (MRI) utilizing newer software. sCT is yet to be explored as a possible alternative to routine CT (rCT). In this study, rCT scans and MRI-derived sCT scans were obtained on a cadaver. Morphometric analysis was performed comparing the 2 scans. The ExcelsiusGPS robot was used to place lumbosacral screws with both rCT and sCT images.

OBSERVATIONS

In total, 14 screws were placed. All screws were grade A on the Gertzbein-Robbins scale. The mean surface distance difference between rCT and sCT on a reconstructed software model was –0.02 ± 0.05 mm, the mean absolute surface distance was 0.24 ± 0.05 mm, and the mean absolute error of radiodensity was 92.88 ± 10.53 HU. The overall mean tip distance for the sCT versus rCT was 1.74 ± 1.1 versus 2.36 ± 1.6 mm (p = 0.24); mean tail distance for the sCT versus rCT was 1.93 ± 0.88 versus 2.81 ± 1.03 mm (p = 0.07); and mean angular deviation for the sCT versus rCT was 3.2° ± 2.05° versus 4.04°± 2.71° (p = 0.53).

LESSONS

MRI-based sCT yielded results comparable to those of rCT in both morphometric analysis and robot-assisted lumbosacral screw placement in a cadaver study.

Open access

Transpedicular Onyx embolization of a thoracic hemangioma with robotic assistance: illustrative case

Andrew M. Hersh, Yike Jin, Risheng Xu, A. Daniel Davidar, Carly Weber-Levine, L. Fernando Gonzalez, and Nicholas Theodore

BACKGROUND

Hemangiomas are common benign vascular lesions that rarely present with pain and neurological deficits. Symptomatic lesions are often treated with endovascular embolization. However, transarterial embolization can be technically challenging depending on the size and caliber of the vessels. Moreover, embolization can result in osteonecrosis and vertebral collapse.

OBSERVATIONS

Here the authors report the first case of a T10 vertebral hemangioma treated with transpedicular Onyx embolization aided by a robotic platform that guided pedicle cannulation and Craig needle placement. An intravenous catheter was attached to the needle and dimethylsulfoxide was infused, followed by Onyx under real-time fluoroscopy. Repeat angiography demonstrated significantly reduced contrast opacification of the vertebral body without compromise of the segmental artery. A T9–11 pedicle screw fixation was performed to optimize long-term stability. The patient’s symptoms improved and was stable at the 6-month follow-up.

LESSONS

Transpedicular embolization of vertebral hemangiomas can be performed successfully under robotic navigation guidance, avoiding complications seen with the intra-arterial approach and allowing for simultaneous pedicle screw fixation to prevent collapse and delayed kyphotic deformity. During the same procedure, a biopsy specimen can be collected for pathology. This technique can help to alleviate patient symptoms while avoiding complications associated with transarterial embolization or open resection.

Restricted access

Creation and preclinical evaluation of a novel mussel-inspired, biomimetic, bioactive bone graft scaffold: direct comparison with Infuse bone graft using a rat model of spinal fusion

Ethan Cottrill, Zach Pennington, Matthew T. Wolf, Naomi Dirckx, Jeff Ehresman, Alexander Perdomo-Pantoja, Christian Rajkovic, Jessica Lin, David R. Maestas Jr., Ashlie Mageau, Dennis Lambrechts, Veronica Stewart, Daniel M. Sciubba, Nicholas Theodore, Jennifer H. Elisseeff, and Timothy Witham

OBJECTIVE

Infuse bone graft is a widely used osteoinductive adjuvant; however, the simple collagen sponge scaffold used in the implant has minimal inherent osteoinductive properties and poorly controls the delivery of the adsorbed recombinant human bone morphogenetic protein–2 (rhBMP-2). In this study, the authors sought to create a novel bone graft substitute material that overcomes the limitations of Infuse and compare the ability of this material with that of Infuse to facilitate union following spine surgery in a clinically translatable rat model of spinal fusion.

METHODS

The authors created a polydopamine (PDA)–infused, porous, homogeneously dispersed solid mixture of extracellular matrix and calcium phosphates (BioMim-PDA) and then compared the efficacy of this material directly with Infuse in the setting of different concentrations of rhBMP-2 using a rat model of spinal fusion. Sixty male Sprague Dawley rats were randomly assigned to each of six equal groups: 1) collagen + 0.2 µg rhBMP-2/side, 2) BioMim-PDA + 0.2 µg rhBMP-2/side, 3) collagen + 2.0 µg rhBMP-2/side, 4) BioMim-PDA + 2.0 μg rhBMP-2/side, 5) collagen + 20 µg rhBMP-2/side, and 6) BioMim-PDA + 20 µg rhBMP-2/side. All animals underwent posterolateral intertransverse process fusion at L4–5 using the assigned bone graft. Animals were euthanized 8 weeks postoperatively, and their lumbar spines were analyzed via microcomputed tomography (µCT) and histology. Spinal fusion was defined as continuous bridging bone bilaterally across the fusion site evaluated via µCT.

RESULTS

The fusion rate was 100% in all groups except group 1 (70%) and group 4 (90%). Use of BioMim-PDA with 0.2 µg rhBMP-2 led to significantly greater results for bone volume (BV), percentage BV, and trabecular number, as well as significantly smaller trabecular separation, compared with the use of the collagen sponge with 2.0 µg rhBMP-2. The same results were observed when the use of BioMim-PDA with 2.0 µg rhBMP-2 was compared with the use of the collagen sponge with 20 µg rhBMP-2.

CONCLUSIONS

Implantation of rhBMP-2–adsorbed BioMim-PDA scaffolds resulted in BV and bone quality superior to that afforded by treatment with rhBMP-2 concentrations 10-fold higher implanted on a conventional collagen sponge. Using BioMim-PDA (vs a collagen sponge) for rhBMP-2 delivery could significantly lower the amount of rhBMP-2 required for successful bone grafting clinically, improving device safety and decreasing costs.

Free access

Anterior cervical discectomy and fusion versus posterior decompression in patients with degenerative cervical myelopathy: a systematic review and meta-analysis

Shahab Aldin Sattari, Mohamad Ghanavatian, James Feghali, Jordina Rincon-Torroella, Wuyang Yang, Risheng Xu, Ali Bydon, Timothy Witham, Allan Belzberg, Nicholas Theodore, and Daniel Lubelski

OBJECTIVE

The optimal surgical approach for patients with multilevel degenerative cervical myelopathy (DCM) remains unknown. This systematic review and meta-analysis sought to compare anterior cervical discectomy and fusion (ACDF) versus posterior decompression (PD) in patients with DCM spanning ≥ 2 levels without ossification of the posterior longitudinal ligament.

METHODS

MEDLINE and PubMed were searched from inception to February 22, 2022. The primary outcomes were Neck Disability Index (NDI), SF-36 Physical Component Summary (PCS), modified Japanese Orthopaedic Association (mJOA) scale, visual analog scale (VAS), and EQ-5D scores. Secondary outcomes were operative bleeding, operative duration, hospital length of stay (LOS), postoperative morbidity (including hematoma, surgical site infection [SSI], CSF leakage, dysphagia, dysphonia, C5 palsy, and fusion failure), mortality, readmission, reoperation, and Cobb angle.

RESULTS

Nineteen studies comprising 8340 patients were included, of whom 4118 (49.4%) and 4222 (50.6%) underwent ACDF and PD, respectively. The mean number of involved spinal levels was comparable between the groups (3.1 vs 3.5, p = 0.15). The mean differences (MDs) of the primary outcomes were the mean of each index in the ACDF group minus that of the PD group. At the 1-year follow-up, the MDs of the NDI (−1.67 [95% CI −3.51 to 0.18], p = 0.08), SF-36 PCS (2.48 [95% CI −0.59 to 5.55], p = 0.11), and VAS (−0.32 [95% CI −0.97 to 0.34], p = 0.35) scores were similar between the groups. While the MDs of the mJOA (0.71 [95% CI 0.27 to 1.16], p = 0.002) and EQ-5D (0.04 [95% CI 0.01 to 0.08], p = 0.02) scores were greater in the ACDF group, the differences were not clinically significant given the minimal clinically important differences (MCIDs) of 2 and 0.05 points, respectively. In the ACDF group, the MDs for operative bleeding (−102.77 ml [95% CI −169.23 to −36.30 ml], p = 0.002) and LOS (−1.42 days [95% CI −2.01 to −0.82 days], p < 0.00001) were lower, the dysphagia OR (11.10 [95% CI 5.43–22.67], p < 0.0001) was higher, and the ORs for SSI (0.43 [95% CI 0.24–0.78], p = 0.006) and C5 palsy (0.32 [95% CI 0.15–0.70], p = 0.004) were lower. The other outcomes were similar between the groups. Overall evidence according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) approach was moderate.

CONCLUSIONS

ACDF and PD are similar regarding functional outcomes. ACDF is beneficial in terms of less bleeding, shorter LOS, and lower odds of SSI and C5 palsy, while the procedure carries higher odds of dysphagia. The authors recommend individualized treatment decision-making.

Free access

Promoting diversity in neurosurgery: a multi-institutional scholarship-based approach

Mareshah N. Sowah, Anthony T. Fuller, Stephanie H. Chen, Barth A. Green, Michael E. Ivan, Henri R. Ford, Gregory J. Zipfel, Brenton Pennicooke, Nicholas Theodore, and Allan D. Levi

Free access

Advancements in the treatment of traumatic spinal cord injury during military conflicts

Andrew M. Hersh, A. Daniel Davidar, Carly Weber-Levine, Divyaansh Raj, Safwan Alomari, Brendan F. Judy, and Nicholas Theodore

Significant advancements in the treatment of spinal cord injury (SCI) were developed in the setting of military conflicts, partly due to the large numbers of injuries sustained by service members. No effective SCI treatment options existed into the early 20th century, and soldiers who sustained these injuries were usually considered untreatable. Extensive progress was made in SCI treatment during and after World War II, as physical therapy was increasingly encouraged for patients with SCI, multidisciplinary teams oversaw care, pathophysiology was better understood, and strategies were devised to prevent wound infection and pressure sores. Recent conflicts in Iraq and Afghanistan have caused a substantial rise in the proportion of SCIs among causes of casualties and wounds, largely due to new forms of war and weapons, such as improvised explosive devices. Modern military SCIs resulting from blast mechanisms are substantively different from traumatic SCIs sustained by civilians. The treatment paradigms developed over the past 100 years have increased survival rates and outcomes of soldiers with SCI. In this paper, the authors review the role of military conflicts in the development of therapeutic interventions for SCI and discuss how these interventions have improved outcomes for soldiers and civilians alike.

Open access

Robot-assisted atlantoaxial fixation: illustrative cases

Amanda N. Sacino, Joshua Materi, A. Daniel Davidar, Brendan Judy, Ann Liu, Brian Hwang, and Nicholas Theodore

BACKGROUND

Placing screws in the high cervical spine can be challenging because of the vital anatomical structures located in that region. Precision and accuracy with screw placement is needed. The use of robotics in the cervical spine has been described before; however, here the authors describe the use of a new robotic setup.

OBSERVATIONS

The authors describe 2 cases of robot-assisted placement of C2 pars screws and C1–2 transarticular screws. The operative plans for each patient were as follows: placement of C2 pars screws with C2–4 fusion for hangman’s fracture and placement of C1–2 transarticular screws for degenerative disease. Intraoperative computed tomography (CT) was used to plan and navigate the screws. Postoperative CT showed excellent placement of hardware. Both patients presented for initial postoperative clinic visits with no recurrence of prior symptoms.

LESSONS

Intraoperative robotic assistance with instrumentation of the high cervical spine, particularly C2 pars and C1–2 transarticular screws, may ensure proper screw placement and help avoid injury.

Free access

Multimodal interventions to optimize spinal cord perfusion in patients with acute traumatic spinal cord injuries: a systematic review

Carly Weber-Levine, Brendan F. Judy, Andrew M. Hersh, Tolulope Awosika, Yohannes Tsehay, Timothy Kim, Alejandro Chara, and Nicholas Theodore

OBJECTIVE

The authors systematically reviewed current evidence for the utility of mean arterial pressure (MAP), intraspinal pressure (ISP), and spinal cord perfusion pressure (SCPP) as predictors of outcomes after traumatic spinal cord injury (SCI).

METHODS

PubMed, Cochrane Reviews Library, EMBASE, and Scopus databases were queried in December 2020. Two independent reviewers screened articles using Covidence software. Disagreements were resolved by a third reviewer. The inclusion criteria for articles were 1) available in English; 2) full text; 3) clinical studies on traumatic SCI interventions; 4) involved only human participants; and 5) focused on MAP, ISP, or SCPP. Exclusion criteria were 1) only available in non-English languages; 2) focused only on the brain; 3) described spinal diseases other than SCI; 4) interventions altering parameters other than MAP, ISP, or SCPP; and 5) animal studies. Studies were analyzed qualitatively and grouped into two categories: interventions increasing MAP or interventions decreasing ISP. The Scottish Intercollegiate Guidelines Network level of evidence was used to assess bias and the Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate confidence in the anticipated effects of each outcome.

RESULTS

A total of 2540 unique articles were identified, of which 72 proceeded to full-text review and 24 were included in analysis. One additional study was included retrospectively. Articles that went through full-text review were excluded if they were a review paper (n = 12), not a full article (n = 12), a duplicate paper (n = 9), not a human study (n = 3), not in English (n = 3), not pertaining to traumatic SCI (n = 3), an improper intervention (n = 3), without intervention (n = 2), and without analysis of intervention (n = 1). Although maintaining optimal MAP levels is the current recommendation for SCI management, the published literature supports maintenance of SCPP as a stronger indicator of favorable outcomes. Studies also suggest that laminectomy and durotomy may provide better outcomes than laminectomy alone, although higher-level studies are needed. Current evidence is inconclusive on the effectiveness of CSF drainage for reducing ISP.

CONCLUSIONS

This review demonstrates the importance of assessing how different interventions may vary in their ability to optimize SCPP.

Free access

Automated prediction of the Thoracolumbar Injury Classification and Severity Score from CT using a novel deep learning algorithm

Sophia A. Doerr, Carly Weber-Levine, Andrew M. Hersh, Tolulope Awosika, Brendan Judy, Yike Jin, Divyaansh Raj, Ann Liu, Daniel Lubelski, Craig K. Jones, Haris I. Sair, and Nicholas Theodore

OBJECTIVE

Damage to the thoracolumbar spine can confer significant morbidity and mortality. The Thoracolumbar Injury Classification and Severity Score (TLICS) is used to categorize injuries and determine patients at risk of spinal instability for whom surgical intervention is warranted. However, calculating this score can constitute a bottleneck in triaging and treating patients, as it relies on multiple imaging studies and a neurological examination. Therefore, the authors sought to develop and validate a deep learning model that can automatically categorize vertebral morphology and determine posterior ligamentous complex (PLC) integrity, two critical features of TLICS, using only CT scans.

METHODS

All patients who underwent neurosurgical consultation for traumatic spine injury or degenerative pathology resulting in spine injury at a single tertiary center from January 2018 to December 2019 were retrospectively evaluated for inclusion. The morphology of injury and integrity of the PLC were categorized on CT scans. A state-of-the-art object detection region-based convolutional neural network (R-CNN), Faster R-CNN, was leveraged to predict both vertebral locations and the corresponding TLICS. The network was trained with patient CT scans, manually labeled vertebral bounding boxes, TLICS morphology, and PLC annotations, thus allowing the model to output the location of vertebrae, categorize their morphology, and determine the status of PLC integrity.

RESULTS

A total of 111 patients were included (mean ± SD age 62 ± 20 years) with a total of 129 separate injury classifications. Vertebral localization and PLC integrity classification achieved Dice scores of 0.92 and 0.88, respectively. Binary classification between noninjured and injured morphological scores demonstrated 95.1% accuracy. TLICS morphology accuracy, the true positive rate, and positive injury mismatch classification rate were 86.3%, 76.2%, and 22.7%, respectively. Classification accuracy between no injury and suspected PLC injury was 86.8%, while true positive, false negative, and false positive rates were 90.0%, 10.0%, and 21.8%, respectively.

CONCLUSIONS

In this study, the authors demonstrate a novel deep learning method to automatically predict injury morphology and PLC disruption with high accuracy. This model may streamline and improve diagnostic decision support for patients with thoracolumbar spinal trauma.